"We get lots of questions about vaporizing, and specifically temperature settings. The idea is to have a high enough setting to boil off the terpenoids you want, without boiling off waxes, or burning off plant matter.

As you can see from the numbers, the best starting point with a vaporizer is about 390F and lower. Different models and designs will need to be individually adjust to fine tune performance. As a general rule, the more heat, the more damage to the terpenoids, so the lower the temperature you can operate at with a satisfactory result, the better."

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I agree with their conclusion, but the article never clarifies that all components begin to vapourize long before they reach their boiling points. I also wish that just once one of these charts would include a source for the information. Where do these numbers come from?

I agree with their conclusion, but the article never clarifies that all components begin to vapourize long before they reach their boiling points. I also wish that just once one of these charts would include a source for the information. Where do these numbers come from?

"We get lots of questions about vaporizing, and specifically temperature settings. The idea is to have a high enough setting to boil off the terpenoids you want, without boiling off waxes, or burning off plant matter.

I agree with their conclusion, but the article never clarifies that all components begin to vapourize long before they reach their boiling points. I also wish that just once one of these charts would include a source for the information. Where do these numbers come from?

but the article never clarifies that all components begin to vapourize long before they reach their boiling points.

Click to expand...

From the publication (emphasis added):

Vaporizer technology may improve the bioavailability of limonene and other compounds, which volatilize around the same temperature as THC (see Figures 1-3). Vaporizers are smoking apparati that heat cannabis to 185°C (365°F), which vaporizes THC but is below the ignition point of combustible plant material. Vaporized cannabis emits a thin gray vapor, whereas combusted cannabis produces a thick smoke. Thus, vaporizers deliver a better canna- binoid-to-tar ratio than cigarettes or water pipes (Gieringer 1996). In a recent study, traces of THC were vaporized at temperatures as low as 140°C (284°F) and the majority of THC vaporized by 185°C (365°F); benzene and other car- cinogenic vapors did not appear until 200°C (392°F), and cannabis combus- tion occurred around 230°C (446°F) (Gieringer 2001).​

There's your range (although it doesn't distinguish between Δ-8 and Δ-9, which each have different volatility points and accounts for some of that spread/range).

I think, regardless of whether the sites know it or not, a lot of the online info comes from McPartland and Russo (2001).

From the publication (emphasis added):

Vaporizer technology may improve the bioavailability of limonene and other compounds, which volatilize around the same temperature as THC (see Figures 1-3). Vaporizers are smoking apparati that heat cannabis to 185°C (365°F), which vaporizes THC but is below the ignition point of combustible plant material. Vaporized cannabis emits a thin gray vapor, whereas combusted cannabis produces a thick smoke. Thus, vaporizers deliver a better canna- binoid-to-tar ratio than cigarettes or water pipes (Gieringer 1996). In a recent study, traces of THC were vaporized at temperatures as low as 140°C (284°F) and the majority of THC vaporized by 185°C (365°F); benzene and other car- cinogenic vapors did not appear until 200°C (392°F), and cannabis combus- tion occurred around 230°C (446°F) (Gieringer 2001).​

There's your range (although it doesn't distinguish between Δ-8 and Δ-9, which each have different volatility points and accounts for some of that spread/range).

The table that @Been Vapin cites does come (IIRC) from Robert Clarke's book which is older (1998) than the paper I cited, so yeah, it would NOT have referenced that. (Plus it pulls data from even older sources.)

Starting on page 111 of the PDF there are tables that include structure, concentration, boiling point, and "properties" (ie effects). The paper does use some of the same sources as the book, but then has a few more. Plus it has the *Slight* advantage of being a few years newer, and thus has a few newer citations. Plus, the paper has been peer-reviewed.

I know a few webpages that cite that publication directly, but an awful lot more copy/paste without reference to the original paper. So its slightly newer and oft-quoted, so that was more my point.

I think, regardlewasn't accurate whether the sites know it or not, a lot of the online info comes from McPartland and Russo (2001).

From the publication (emphasis added):

Vaporizer technology may improve the bioavailability of limonene and other compounds, which volatilize around the same temperature as THC (see Figures 1-3). Vaporizers are smoking apparati that heat cannabis to 185°C (365°F), which vaporizes THC but is below the ignition point of combustible plant material. Vaporized cannabis emits a thin gray vapor, whereas combu d cannabis produces a thick smoke. Thus, vaporizers deliver a better canna- binoid-to-tar ratio than cigarettes or water pipes (Gieringer 1996). In a recent study, traces of THC were vaporized at temperatures as low as 140°C (284°F) and the majority of THC vaporized by 185°C (365°F); benzene and other car- cinogenic vapors did not appear until 200°C (392°F), and cannabis combus- tion occurred around 230°C (446°F) (Gieringer 2001).​

There's your range (although it doesn't distinguish between Δ-8 and Δ-9, which each have different volatility points and accounts for some of that spread/range).

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That vaporizer study used one of the earlier vaporizers that wasnt accurate in temperature, as far as the temperature of the air in the bowl. I wish I can remember the name of it but, it was a handheld, wand type vaporizer that you put over a glass bowl. I'm sure someone remembers the name but, if I remember correctly it built up heat and would burn the herbs sometime so that is probably why the temperature is reported being so low for boiling majority of THC in that study. Damn I wish I can remember the name of that vaporizer so I can post a picture. The company who made it came out with one of the first portable, battery operated vaporizers in 2006.

That vaporizer study used one of the earlier vaporizers that wasnt accurate in temperature, as far as the temperature of the air in the bowl. I wish I can remember the name of it but, it was a handheld, wand type vaporizer that you put over a glass bowl. I'm sure someone remembers the name but, if I remember correctly it built up heat and would burn the herbs sometime so that is probably why the temperature is so low for boiling majority of THC in that study. Damn I wish I can remember the name of that vaporizer so I can post a picture. The company who made it came out with one of the first portable, battery operated vaporizers in 2006.

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They used two vaporizers. The one you are trying to remember is the Tilt:

​

It's basically a BC Vaporizer. The other was the M1 Volatizer, which was basically a heater element that you placed over a bong bowl:

​

Volatizer is still in business and sells the M2, which is not much different from the M1.

Medical marijuana patients may protect themselves from harmful toxins in marijuana smoke by inhaling their medicine using an electric vaporizer, according to results of a study by California NORML and MAPS (Multidisciplinary Association for Psychedelic Studies).

The study showed that it is possible to vaporize medically active THC by heating marijuana to a temperature short of the point of combustion, thereby eliminating or substantially reducing harmful smoke toxins that are normally present in marijuana smoke. Vaporizers may therefore substantially reduce what is widely regarded as the leading health hazard of marijuana, namely respiratory harm due to smoking.

Details of the study are published in D. Gieringer, "Cannabis Vaporization: A Promising Strategy for Smoke Harm Reduction," Journal of Cannabis Therapeutics Vol. 1#3-4: 153-70 (2001). Reprints available for $5 from California NORML, 2261 Market St. #278A, San Francisco CA 94114.

NORML and MAPS sponsored the study in the hopes of helping medical marijuana patients and others reduce the health risks of smoking. The hazards of smoking were cited as a major obstacle to approval of natural cannabis by the Institute of Medicine in its 1999 report, "Marijuana and Medicine." However, the IOM report failed to note the possibility of vaporization.

The NORML-MAPS study tested a device called the M1 Volatizer, an aromatherapy vaporizer
developed by Alternative Delivery Systems, Inc. It consisted of an electric heating element in a chamber that radiates heat downwards over a sample of marijuana sitting in a standard pipe or "bong" bowl. Output from the vaporizer was analyzed and compared to smoke produced by combusting the sample with a flame.

The vaporizer produced THC at a temperature of 185° C. (365° F.) while completely eliminating three measured toxins - benzene, a known carcinogen, plus toluene and naphthalene. Carbon monoxide and smoke tars were both qualitatively reduced by the vaporizer, but additional testing is needed to quantify the extent of the decrease.

Although the study was not designed to detect the highly carcinogenic tars known as polycyclic aromatic hydrocarbons, which are thought to be a leading culprit in smoking-related cancers, there was good reason to believe that they were suppressed, since they normally form at much higher temperatures of combustion.

When vaporized, the marijuana emitted a thin gray vapor and was left with a green to greenish-brown "toasted" appearance, whereas the combusted sample produced thick smoke and turned to ash.

Significant amounts of benzene began to appear at temperatures of 200° C. (392° F), while combustion occurred around 230° (446°F) or above. Traces of THC were in evidence as low as 140° C. (284° F).

Further details of the study will be published in a forthcoming issue of the Journal of Cannabis Therapeutics.

Medical marijuana patients may protect themselves from harmful toxins in marijuana smoke by inhaling their medicine using an electric vaporizer, according to results of a study by California NORML and MAPS (Multidisciplinary Association for Psychedelic Studies).

The study showed that it is possible to vaporize medically active THC by heating marijuana to a temperature short of the point of combustion, thereby eliminating or substantially reducing harmful smoke toxins that are normally present in marijuana smoke. Vaporizers may therefore substantially reduce what is widely regarded as the leading health hazard of marijuana, namely respiratory harm due to smoking.

Details of the study are published in D. Gieringer, "Cannabis Vaporization: A Promising Strategy for Smoke Harm Reduction," Journal of Cannabis Therapeutics Vol. 1#3-4: 153-70 (2001). Reprints available for $5 from California NORML, 2261 Market St. #278A, San Francisco CA 94114.

NORML and MAPS sponsored the study in the hopes of helping medical marijuana patients and others reduce the health risks of smoking. The hazards of smoking were cited as a major obstacle to approval of natural cannabis by the Institute of Medicine in its 1999 report, "Marijuana and Medicine." However, the IOM report failed to note the possibility of vaporization.

The NORML-MAPS study tested a device called the M1 Volatizer, an aromatherapy vaporizer
developed by Alternative Delivery Systems, Inc. It consisted of an electric heating element in a chamber that radiates heat downwards over a sample of marijuana sitting in a standard pipe or "bong" bowl. Output from the vaporizer was analyzed and compared to smoke produced by combusting the sample with a flame.

The vaporizer produced THC at a temperature of 185° C. (365° F.) while completely eliminating three measured toxins - benzene, a known carcinogen, plus toluene and naphthalene. Carbon monoxide and smoke tars were both qualitatively reduced by the vaporizer, but additional testing is needed to quantify the extent of the decrease.

Although the study was not designed to detect the highly carcinogenic tars known as polycyclic aromatic hydrocarbons, which are thought to be a leading culprit in smoking-related cancers, there was good reason to believe that they were suppressed, since they normally form at much higher temperatures of combustion.

When vaporized, the marijuana emitted a thin gray vapor and was left with a green to greenish-brown "toasted" appearance, whereas the combusted sample produced thick smoke and turned to ash.

Significant amounts of benzene began to appear at temperatures of 200° C. (392° F), while combustion occurred around 230° (446°F) or above. Traces of THC were in evidence as low as 140° C. (284° F).

Further details of the study will be published in a forthcoming issue of the Journal of Cannabis Therapeutics.

I agree with their conclusion, but the article never clarifies that all components begin to vapourize long before they reach their boiling points. I also wish that just once one of these charts would include a source for the information. Where do these numbers come from?

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Your question is how they found each boiling point temperature? Because there is a study with every cannabinoid and its boiling temperature, i can't find it but i found it many times while surfing the web so i'm guessing you have found it already.

Your question is how they found each boiling point temperature? Because there is a study with every cannabinoid and its boiling temperature, i can't find it but i found it many times while surfing the web so i'm guessing you have found it already.

I think it was one study from Ethan Russo.

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No, my question was rhetorical. I was expressing frustration about the way charts like this are tossed around with no thought whatsoever about their accuracy. Since there are versions with various different temperatures, people should be careful of relying on them to target specific components through precise temperature control—although that concept is usually so poorly understood I'm probably tilting at windmills.

Yes, I do have a fine collection of cannabis studies related to vapourizing, including McPartland & Russo, which Nigel linked earlier but I've had it for years. They don't describe how the temperatures are derived either. They compiled them from various sources, just as the Clarke book apparently did.

Okay, i agree with you. I'd like the research to go further into the extraction process again, with the vaporizers out there today and the data already available, great breakthroughs could happen in understanding how the different cannabinoids affect us and our physiology as well as further understanding what happens chemically to the plant while it is being extracted.

This could help medical patients to better administer their medicine and also know exactly what could happen if one abuses the plant.

Because it eliminates combustion. The Herbalaire's design extracts thoroughly, so you don't need a higher temperature. It's a common misconception that you have to reach the boiling point of a compound to extract it. All components start to vapourize at temperatures well below the boiling point. You can turn a pot of water completely into vapour by maintaining a temperature of 90°C (194°F) or even much lower. Cannabis compounds are no different.

All components start to vapourize at temperatures well below the boiling point ... Cannabis compounds are no different.

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very true, but low temps don't give me a tube full of vapor.

it's hard to know what other vaporizers are actually measuring or running at. i know when mine says 420°F, that an inhale sweeps my herb with an air flow that raises the herb from 370°F to 420°F, and the draw tube goes white.

Yes they do, it's just not as thick. Vapour doesn't have to be visible. The association of thick white clouds with better vapour is another widely-held misconception but it isn't one that will be corrected any time soon. The thickness of the vapour is directly related to the temperature and not the potency. Hotter thus thicker vapour contains more of the particulate matter that provides a nucleus for condensation, hence visibility, but is also responsible for higher levels of irritation. This plays into yet another myth: "cough to get off."

yeah, when i cough i know the temp is too high -- drop it 5°F and the cough stops.

The thickness of the vapour is directly related to the temperature

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... and the amount of airflow.

re: potency ... well, i find the thickness of the vapor very much depends on the quality of the herb (dankosity) at any given temperature. with herb dankosity at the high end of the scale, i am quite satisfied (i.e. tube full of white vapor) at a setting of 385°F (again, the herb is sitting at 335°F, and the inhale brings it up to 385°F), but for most of the ditch weed i can find, the 420°F is necessary.

and it will take some convincing for me to accept that invisible vapor can be as satisfying as white walling my tube. but it's been decades since i've had access to Maui Wowwie.

which is all just to reiterate that i would find 400°F too low -- if that's what the temp really is.